Several scientific studies have found that while there might be improvements from practicing the IQ test itself and becoming used to the question format, there is unlikely to be any general boost to your abilities beyond the specific type of questions you train for as your general intelligence remains fairly stable from adolescence onward.
Therefore, most psychologists believe IQ scores primarily measure relatively stable individual differences in general cognitive abilities that are less impacted by practice effects beyond specific types of tasks and may reflect genetic dispositions for intellectual functioning.